Drive mechanism for quilting machines



A ril 7, 1964 D. R- cAsH 3,127,858

DRIVE MECHANISM FOR QUILTING MACHINES Filed April 4, 1962 2 Sheets-Sheet1 lllllllllllln I N VEN TOR. mwo I. (45H,

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April 7, 1964 DRIVE MECHANISM FOR QUILTING MACHINES 2 Sheets-Sheet 2Filed April 4, 1962 INVENTOR.

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l I 0 r United States Patent 3,127,858 DRIVE MECHANISM FOR QUitLTlNGMACHINES David R. Cash, Louisville, Ky, assignor to James Cash Machine(30., Louisville, Ky, a corporation of Kentucky Filed Apr. 4, 1%2,Ei'er. No. 185,041 4 Ciaims. (*Ci. lib-118) This invention relatesgenerally to quilting machines, and particularly to a novel means forproviding a positive drive ond obtaining intricate quilt stitchpatterns.

In many bedding components, including mattresses as well as bed covers,quilting is found desirable both from the appearance and functionalstandpoints. Quilting can be accomplished by machines which are wellknown in the art. However, the nature of the quilt stitch pattern hasheretofore been quite limited by the inability of available machines toprovide patterns having sharp changes of direction or having crossingstitch paths.

While efforts have been made to overcome the inability of quiltingmachines to produce patterns having intersecting rows of stitches,little or no success has been achieved heretofore. One significantdisadvantage of available machinery is the fact that the stitch theyproduce is irregular, particularly at sharp changes of direction.

It is a general object of the present invention to provide means forincreasing versatility of quilting machines.

It is a further object of the present invention to provide means forensuring regularity of stitches in an intricate stitch pattern forquilting.

It is a still further object of this invention to provide means forachieving the foregoing objects and enabling the same to be achieved inthe execution of a quilt stitching operation where the quilt patternincludes a number of intersecting rows of stitches.

It is a still further object of the present invention to provide meansfor achieving the foregoing objects, which means can be employed in avariety of existing quilting machines.

Described briefly, a typical embodiment of the present inventionincludes a pattern track having a base plate and intersecting rows ofupstanding teeth in an endless pattern secured to the plate. A noveltracer head is provided with an input shaft to be coupled to thequilting machine drive motor and an output drive gear engaging thepattern track. The head incorporates novel drive means for maintainingengagement between the drive gear and the track while at the same timeavoiding torques which would tend to interfere with the retention ofproper engagement with the track.

The full nature of the invention will be understood from theaccompanying drawings and the following description and claims:

FIG. 1 is a perspective schematic illustration of an automatic quiltingmachine of the type employed in the manufacture of quilted mattresses.

FIG. 2 is a top plan view of a pattern track according to a typicalembodiment of this invention.

FIG. 3 is a side elevation, partially in section, of the novel drivehead of the present invention engaged with a portion of the patterntrack, all of the elements of FIG. 3 being greatly enlarged bycomparison with FIG. 1.

FIG. 4 is a vertical section taken along the line 4-4 of FIG. 3.

FIG. 5 is an enlarged fragmentary side elevation illustrating details ofengagement of the track drive gear and track at a track intersection.

FIG. 6 is afragmentary section taken along line 6-6 of FIG. 5 with thedriving gear omitted and illustrating a second aspect of the trackintersection.

FIG. 7 is an enlarged fragmentary illustration of the drive gear andretainer assembly.

Quilting Machines in General (FIG. 1)

Typical quilting machines include a stationary frame having uprights 12and 13 connected by lower, intermediate, and upper cross members 14, 16and 17, respectively. A sewing machine 13 is mounted to the upper crossmember and driven by a shaft 19 extending from the upright 12 and drivenby a motor therein. The upper sewing head 21 of the sewing machine islocated in the usual location with respect to the material to be sewnand includes the sewing needle.

A movable carriage 22 is mounted to the stationary frame in such amanner that it is free to move in any direction in a horizontal plane.For movements parallel to the frame cross members 14 etc. support tracks23 and 24 which rest on the floor and are secured to the uprights 12 and13, carry the roller wheels 26 at each end of the carriage. Wheels 26provide the support for the carriage lower support frame having side:members 27. The side members 27 support the wheels 28 which are .mountedto the carriage upper support frame 29 to allow movements of thecarriage perpendicular to the cross member 14.

On the top frame of the carriage, materials 31 to be sewn together in aquilt pattern are held in place by the clamps 32. These materials, forexample, might include a layer of ticking, a layer of felt, a layer ofpadding material and another layer of felt and a web base.

Immediately below the materials to be sewn, and mounted to the crossmember 16 in alignment with the head 21 of the sewing machine, is theusual thread locking mechanism (not shown in the drawing).

A pattern track 33 is removably secured to the carriage upper supportframe 29. The pattern track includes a base plate with a track 34thereon which is laid out in the pattern of the quilt stitch patterndesired.

A drive head 36 has a drive member 37 engaging the track 34 at a pointimmediately below the drive shaft 38. The shaft 38 is driven from asuitable transmission 39 receiving its drive from the drive motor 41,both the transmission and drive motor being mounted to one of the crossmembers and, therefore, stationary. Thus, power is coupled from themotor 41 to the drive member 37 whereby it is capable of driving thetrack and thereby the carriage in the many different directions requiredto obtain the desired quilt stitching pattern. Of course, the mountingof the drive head 36 to the shaft 38 permits the head to turn towhatever extent is necessary as it drives the pattern track.

Pattern Track (FIGS. 2-6) According to the present invention, thepattern track assembly includes a base plate 51 and elongate strips 52mounted on edge thereon and provided with upstanding teeth 53 at theupper margin thereof. Many forms of teeth or other types of positivedrive elements including pins and apertures, for example, may be foundsuitable. However, an involute form is excellent in which case thestrips 52 may be understood to provide an involute gear rack. Theexpressions tooth and teeth will, however, be used generically in theclaims herein and understood to contemplate other types of positivedrive elements.

The teeth extend in succession in a layout having the pattern desired inthe quilt. The succession of teeth is endless so that the drive head canbegin driving the carriage at any point on the track and continue todrive the pattern until the quilting is completed without ever retracingthe stitch.

In FIG. 2, taking the point 56 as a starting point and assuming thetrack is driven in the direction of arrow 57, the movement of the headwith respect to the pattern track along the leg 58 of the track, is inthe opposite direction shown by arrow 59. The head then negotiates theturn 61 and drives along the straight leg 62. The drive continues backand forth to the opposite end of the pattern track and then crosswisethereof as it follows the serpentine layout of the track. It is thetrack, of course, which is moved in horizontal translation and not thehead. It should be understood that a wide variety of patterns other thanthat shown in FIG. 2 may be employed. The rows of teeth need not bestraight and intersections of rows of teeth need not be right-angleintersections.

In FIG. 5, one view of an intersection such as intersection 63 of FIG.2, is illustrated. A tooth 64 is provided at the precise center of theintersection and the next adjacent tooth 53a on one side and 53b on theother side is placed from the center tooth 64 a distance equal to thesum of the length of tooth 53 and two tooth spaces 66. This is toprovide for passage of the drive member (to be described hereinafter)across the intersection in a direction perpendicular to the direction ofthe row of teeth illustrated. It will be recognized, that by use of theconstruction illustrated in FIG. 5, a long strip 52 of material withsuitable cut aways 67 and 68 at the intersections can be welded to theplate 51 and thereby facilitate the manufacture of the pattern track.

From the foregoing it will be appreciated that my pattern track assemblycomprises: a base plate 51; and an elongate track 52. secured to saidbase plate, said track being composed of an elongate strip of material,also designated 52. This strip has straight sections 58 and 62, curvedsections 61 and intersections 63 respectively corresponding to thestraight and curved sections and intersections of a desiredquilt-stitching pattern. The strip 52 presents, between intersections,an upper edge notched to provide a uniform succession of teeth 53. Thestrip has, at one intersection, one track section extending continuouslythrough the intersection (as indicated at the bottoms of cut aways 67and 68 in FIG. 5) with one tooth 64 (on that extension) centered on thatintersection and with the upper margin of that extension cut away toeliminate one tooth on each side of said centered tooth. At the sameintersection, the other track section of the strip has one toothcentered on that intersection and is arranged with its upper margin cutaway to eliminate the centered tooth and one tooth on each side thereof.

In FIG. 6, which views the intersection 63 at 90 with respect to FIG. 5,it will be observed that to obtain the sections of track which cross thetrack 52, it is convenient to provide them in separate sections 52a and52b welded to the base plate.

Drive Head (FIGS. 3 and 4) The drive head 70 includes a housing 71 withthe cover plate 72 secured thereto by the screw 73. The drive shaft 74is mounted in the housing by means of a bearing 71a (partially shown).It will be recognized, therefore, that the housing is free to rotatewith respect to the shaft 74 and vice versa, but is not free to moveaxially with respect to the shaft 74 by any more than the necessarybearing tolerance. The upper end of the shaft 74- is provided with akeyway 74a whereby rotational drive can be provided from the motor 41.

A worm tooth 75 (usually 24:1) is provided at the lower end of the shaft74 and drives the gear 76 mounted for rotation in the housing on shaft77. By the employment of worm and gear in this fashion, the torque onthe housing caused by the input drive is made negligible.

A second shaft 78 supports the drive member 79 for rotation in thehousing in a plane on the axis of the input shaft 74. The shaft 78intersects the axis of shaft 74, whereby the drive point between thedrive member 79 and the pattern track is in line with the axis of inputshaft 74, again avoiding any torque on the housing resulting from thedrive.

Summarizing the foregoing description of the drive head 70, it will beappreciated: that I provide a motordriven follower of the type used forshifting a quiltingmachine carriage means in accordance with thestraight and curved sections of a pattern forming track 52 traversed bythe drive head or follower 70. This follower comprises: a followerhousing 71; and a drive train supported by the housing. The drive trainincludes: a power input shaft 74 extending vertically downward into saidhousing; a track-engaging gear 79 mounted for rotation about thetransverse axis of a shaft 78; interconnecting means for driving thetrack-engaging gear 79 from shaft 74 (including worm 75, shaft 77, gearand sprocket combination 76 and 88, chain 89 and sprocket and gearcombination 91 and 79 on shaft 78); a pair of wheel-like flanges 81, 82,one mounted on each side of the trackengaging gear 79 for rotation aboutthe axis of shaft 78, one of said flanges being axially movable inrelation to the other; and resilient means 83 interposed between aninner wall of the housing and movable flange 82 to bias that flangetoward the other flange 81.

While the drive member 79 may employ transverse pins to engage the trackteeth, it is most convenient to use an involute gear, a 20:12 gear beingwell suited for the purpose.

Gear 79 is flanked on opposite sides by wheel-like flanges 81 and 82.These flanges maintain the alignment of the gear with the track. Toaccommodate a turn in the track, the inside faces 81a and 82a of theflanges are convex in form and the flange 82 is allowed to move axiallywith respect to the flange 81. To maintain the minimum spacing betweenthe flanges at all times when the head is driving a straight portion oftrack and permit separation to the extent necessitated by the degree ofcurvature where a curved portion of track is encountered, a spring 83'is disposed between the housing wall 84 and the flange 82.

A convenient construction of the drive member and flange unit isillustrated in FIG. 7. The gear 79 is slightly inset into a circularcavity 81b in the flange 81 and secured. to the flange by means of pins86. Flange hub 87 is keyed to the shaft 7 8 and secured by a setscrew.

A similar cavity 82b is provided in flange 82 and the face of gear 79may lie in abutting relation to the face of cavity 82b when the gear isoperating on a straight portion of track. By virtue of the sliding fitof the flange hub 820 on shaft 78, the spacing of the flanges canincrease as the gear encounters a curve in the track. By Way of example,a typical amount of movement encountered may be from 55 to 7 of an inch.

A sprocket 88, secured to shaft 77, is driven by the gear 76 and driveschain 89 to drive sprocket 91 secured to shaft 78 which in turn drivesthe gear 79. A chain tensioning idler 92 is adjustably mounted in thehousing 71 to provide suitable chain tension.

From study of the illustrated embodiment of FIG. 4 it can be appreciatedthat the drive head is statically balanced with respect to a planeincluding the axis of the input shaft and perpendicular to shafts 77 and78. This is accomplished by location of parts and providing a thickersection in wall 84 than is provided in the facing wall of the housing.Thus wall 84 and the spring 83 balance the weight of the sprockets,chain and idler shaft. The tracking capability of the drive head isthereby improved. It should be understood, of course, that the housingneed not be of the specific shape illustrated.

From FIG. 5, an interesting detail of the drive at intersections can beobserved. Assuming that the tnack is being driven in the direction ofarrow 96, drive gear 79 is rotating clockwise as indicated by arrow 97.To avoid applying an excessive dnive load on the center tooth 64', thegear and track teeth are cut and spaced such that gear tooth 79a entersinto driving contact with rack tooth 53b before gear tooth 79bdiscontinues driving contact with rack tooth 53a. Center tooth 64 canthus function s,127,ees

principally for alignment by cooperation with the retainer flanges (Si,8 2, FIG. 4).

Conclusion it will be appreciated from the foregoing description, thatby the provision of positive drive means, both in the pattern track andin the drive head, the stitch pattern obtained in a quilting machineemploying the present invention will have uniform length. By virtue ofthe special provisions taken to avoid a torque on the housing '71resulting from power transmission, true tracing of the pattern by thedrive head is obtained, avoiding wavering of the stitch and assuringprecise control over all intersections. The additional provision of thenovel flanged drive member permits accurate and free negotiation ofcurves and turns in the track without sacrificing any of the precisionof the tracking and accordingly of stitching. In addition to thiscapability to accurate tracing and maintenance of precise stitch lengthcontrol, the present invention permits the tracing of patterns havingrelatively sharp changes in direction and having inter secting lines ofstitches.

While the invention has been disclosed and described in some detail inthe drawings and foregoing description, they are to be considered asillustrative and not restrictive in character, as modifications mayreadily suggest themselves to persons skilled in this art and within thebroad scope of the invention, reference being had to the ap pendedclaims.

The invention claimed is:

1. A drive mechanism for a quilting machine or the like, comprising:

(A) a pattern track assembly including (1) a base plate and ((2) a tracksecured to said base plate and arranged to present an elongate row ofteeth extending in a pattern having straight sections and curvedsections; and

(B) a drive head having (1) a track tooth-engaging member,

(2) an input shaft,

(3) drive means coupling said tooth-engaging member to said input shaftand including (a) a pair of wheel-like flanges arranged,

one on each side of said tooth-engaging member, to maintain theengagement of said member with said track,

(1) said flanges being relatively movable toward and away from eachother, and

(4) resilient means biasing one flange toward the other.

2. A motor-driven follower of the type used for shifting a quiltingmachine carriage means in accordance with iii the straight and curvedsections of a pattern-forming track traversed by the following,comprising:

(A) a follower housing; and (B) a drive train supported by said housingand ineluding (1) a power input shaft extending into said hous- (2) atrack-engaging gear mounted for rotation about a transverse axis, (3)interconnecting means for driving said trackengaging gear from saidinput shaft, and (4) a pair of wheel-like flanges,

'(a) one mounted on each side of said gear for rotation about the axisof said shaft, (b) one of said flanges being axially movable in relationto the other to provide a variable axial spacing between said flanges.3. The follower of claim 2 including (A) resilient means interposedbetween said housing and said movable flange to bias said movable flangetoward said other flange. 4. A pattern track for a quilting machine orthe like comprising:

(A) a base plate; and (B) an elongate track secured to said base plate,

(1) said track being composed of an elongate strip of material (a) whichhas straight and curved sections and intersections corresponding to thestraight and curved sections and intersections of a desiredquiltstitching pattern, (b) which presents, between intersections, anupper edge notched to provide a uniform succession of teeth, and (c)which has, at one intersection,

.( 1) one track section of the strip extending continuously through theintersection with one tooth centered on that intersection and with itsupper margin cut away to eliminate one tooth on each side of saidcentered tooth and (2) the other track section of the strip arrangedwith one tooth centered on that intersection and with its upper margincut away to eliminate the centered tooth and one tooth on each sidethereof.

References Cited in the file of this patent UNITED STATES PATENTS3,046,921 S'chwarzberger July 31, 1962

1. A DRIVE MECHANISM FOR A QUILTING MACHINE OR THE LIKE, COMPRISING: (A)A PATTERN TRACK ASSEMBLY INCLUDING (1) A BASE PLATE AND (2) A TRACKSECURED TO SAID BASE PLATE AND ARRANGED TO PRESENT AN ELONGATE ROW OFTEETH EXTENDING IN A PATTERN HAVING STRAIGHT SECTIONS AND CURVEDSECTIONS; AND (B) A DRIVE HEAD HAVING (1) A TRACK TOOTH-ENGAGING MEMBER,(2) AN INPUT SHAFT, (3) DRIVE MEANS COUPLING SAID TOOTH-ENGAGING MEMBERTO SAID INPUT SHAFT AND INCLUDING (A) A PAIR OF WHEEL-LIKE FLANGESARRANGED, ONE ON EACH SIDE OF SAID TOOTH-ENGAGING MEMBER, TO MAINTAINTHE ENGAGEMENT OF SAID MEMBER WITH SAID TRACK, (1) SAID FLANGES BEINGRELATIVELY MOVABLE TOWARD AND AWAY FROM EACH OTHER, AND (4) RESILIENTMEANS BIASING ONE FLANGE TOWARD THE OTHER.